A new report issued by the International Osteoporosis
Foundation (IOF) and published in the scientific journal
Osteoporosis International1, shows that populations
across the globe are suffering from the impact of
low levels of vitamin D. The problem is widespread
and on the increase, with potentially severe repercussions
for overall health and fracture rates.

Compiled by IOF's expert working group on nutrition,
the report reviews the scope and causes of low vitamin
D levels in six regions: Asia, Europe, Latin America,
Middle East and Africa, North America and Oceania.
Regional reports are available on the IOF website

Vitamin D is mainly produced in the skin upon exposure
to sunlight, and, to a lesser extent, is derived from
nutritional sources. It plays an important role, through
its influence on calcium levels, in the maintenance
of organ systems, and is needed for normal bone mineralization
and growth. Suboptimal levels of vitamin D may lead
to increased risk of osteoporosis and hip fracture
and, in severe cases, to the development of rickets,
a softening of bones in children that can lead to
skeletal fractures and deformity.

Although there is ongoing debate as to what constitutes
the optimal level of vitamin D, the report shows that
regardless of whether it is defined at 50nmol/L or
75nmol/L, vitamin D status is seriously inadequate
in large proportions of the population across the
globe.

The main risk factors for low vitamin D levels include
older age, female sex, lower latitudes, winter season,
darker skin pigmentation, less sunlight exposure,
dietary habits, and the absence of vitamin D fortification
in common foods. Further factors include the increase
in urbanization, where people tend to live and work
indoors, as well as cultural practices that tend towards
sun avoidance and the wearing of traditional clothing
that covers the skin. The severity of the problem
in Middle East and South Asia arises from the combination
of several of these risk factors.

These findings suggest that prevention strategies
must be initiated at the national level - especially
given the increasing ageing of populations in many
regions of the world. National plans of action should
encourage safe, limited exposure to sunlight and improved
dietary intake of vitamin D, whilst considering fortification
of foods as well.